welcome to the painting =D
Paradigm is right, but also another way to do what you're talking about, if the areas are recessed, is to paint them first and then carefully drybrush a layer on top. I'd still recommend a wash, it helps it stand out. Note this will also work if the lines are raised for instance, but you will need to paint the underlying area first, instead, and then carefully drybrush the lines. Drybrushing catches the higher edges of something, which makes it a good technique for this sort of thing.
If the raised areas (not the lines) are big enough it's also possible to simply paint them after painting the lines and applying a wash. This can give you two tones as well.
here is a drybrush tutorial:
https://www.youtube.com/watch?v=QaEKiuCr7kg
also, his how to use washes:
https://www.youtube.com/watch?v=Ke2UMbMPN9w
I strongly recommend his channel, it's really good! You can also look up Warhammer TV to find
GWs painting tutorials
Good luck and happy painting!